Phase Constitution and Heat Treatment Behavior of Ti-7mass% Mn-Al Alloys

2010 ◽  
Vol 654-656 ◽  
pp. 855-858 ◽  
Author(s):  
Masahiko Ikeda ◽  
Masato Ueda ◽  
R. Matsunaga ◽  
Mitsuo Niinomi
Keyword(s):  
Heat Treatment ◽  
Electrical Resistivity ◽  
Titanium Alloys ◽  
Beta Phase ◽  
Al Alloys ◽  
Omega Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Al Content ◽  
Solution Treated

Titanium exhibits many attractive properties. It is considered to be ubiquitous since it has the 9th-highest Clarke number of all the elements. However, the principal beta-stabilizing elements for titanium can be very expensive, making many titanium alloys expensive. Manganese is a beta stabilizer for titanium alloys and it is also considered to be ubiquitous since it has the 11th-highest Clarke number of all the elements. The behavior of Ti-Mn alloys during heat treatment has been investigated and it was found that in some alloys the isothermal omega phase is precipitated. Because this phase can lead to brittleness, it is very important to suppress its precipitation. Since it is well-known that aluminum suppresses isothermal omega precipitation, we investigated the effect of adding aluminum using Ti-7mass% Mn-0, 1.5, 3.0 and 4.5mass% Al alloys by performing electrical resistivity, Vickers hardness, and X-ray diffraction measurements. In solution-treated and water-quenched 0 and 1.5 alloys, only beta phase was identified, while hcp martensite and bate phase were identified in 3.0 and 4.5Al alloys. The resistivities at room and liquid-nitrogen temperatures were found to increase monotonically with increasing Al content. Isothermal  precipitation was suppressed by aluminum addition, while alpha precipitation was accelerated by Al addition.

Effect of Al Addition on Phase Constitution and Heat Treatment Behavior in Ti-8.5mass%Mn-1mass%Fe-Al Alloys

2014 ◽  
Vol 783-786 ◽  
pp. 562-567 ◽  
Author(s):  
Masahiko Ikeda ◽  
Masato Ueda ◽  
Yoshinori Sumi ◽  
Mitsuo Niinomi
Keyword(s):  
Heat Treatment ◽  
Vickers Hardness ◽  
Beta Phase ◽  
Al Alloys ◽  
Omega Phase ◽  
X Ray Diffraction ◽  
Phase Constitution ◽  
Al Content ◽  
Fe Alloys ◽  
Iron And Manganese

Titanium is considered to be a ubiquitous element since it has the 9th-highest Clarke number of all elements. Iron and manganese can also be used as beta stabilizers for Ti alloys, and can be considered to be ubiquitous because of their 4th- and 11th-highest Clarke numbers, respectively. However, investigations into the behavior of Ti-Mn-Fe alloys during heat treatment have shown that in some alloys, the isothermal omega phase is precipitated. Because this phase can lead to brittleness, it is very important to prevent it from forming. It is well known that aluminum can suppress the precipitation of the isothermal omega phase. Thus, in the present study, we investigated the effect of Al content on the phase constitution and heat-treatment behavior of Ti-8.5mass%Mn-1mass%Fe-0 to 4.5mass%Al alloys using electrical resistivity, Vickers hardness, and X-ray diffraction measurements. In all solution-treated and quenched alloys, only the beta phase was identified, thus confirming the suppression of omega-phase precipitation. The resistivity was found to increase monotonically with Al content, while the Vickers hardness decreased up to 3 mass% Al and then remained constant.

Development and Research of Low-Cost Titanium Alloys, Especially Case of Japan

2016 ◽  
Vol 879 ◽  
pp. 119-124 ◽  
Author(s):  
Masahiko Ikeda ◽  
Masato Ueda
Keyword(s):  
Heat Treatment ◽  
Vickers Hardness ◽  
Low Cost ◽  
Beta Phase ◽  
Omega Phase ◽  
X Ray Diffraction ◽  
Practical Applications ◽  
Al Content ◽  
Ti Alloys ◽  
Fe Alloys

Titanium (Ti) exhibits many attractive properties that enable practical applications. It is also considered to be a ubiquitous element, since it has the ninth highest Clarke number among all the elements. However, the principal beta-stabilizing elements for Ti, molybdenum and vanadium, can be very expensive, and so many Ti alloys are also costly. For this reason, less expensive alloying elements would be preferable. Iron (Fe) and manganese (Mn) are beta stabilizers for Ti alloys that are readily available, since they have the fourth and eleventh highest Clarke numbers, respectively. Furthermore, since Fe has a large diffusion coefficient in the beta phase of Ti, precipitation of the omega phase occurs more quickly when Fe is added. The behaviors of Ti-Mn and Mn-Fe alloys during heat treatment have been investigated and it has been found that, in some alloys, the isothermal omega phase is precipitated. Because this phase can lead to brittleness of the alloy, it is very important to suppress its precipitation. Since it is well known that aluminum (Al) suppresses isothermal omega precipitation, the present work investigated the effects of Al content on the phase constitution and heat treatment behavior of Ti-8.5 mass%Mn-1 mass%Fe-0, 1.5, 3.0 and 4.5 mass%Al alloys using electrical resistivity, Vickers hardness, and X-ray diffraction measurements. In the case of each of these alloys, whether solution-treated or water-quenched, only the beta phase was identified. The resistivities at room and liquid nitrogen temperatures were found to increase monotonically with Al content, while the Vickers hardness decreased up to 3 mass% Al and then remained constant. The addition of Al was found to suppress omega precipitation.

Phase Constitution and Heat Treatment Behavior of Zr-Nb Alloys

2007 ◽  
Vol 561-565 ◽  
pp. 1435-1440 ◽  
Author(s):  
Masahiko Ikeda ◽  
Tsuyoshi Miyazaki ◽  
Satoshi Doi ◽  
Michiharu Ogawa
Keyword(s):  
Heat Treatment ◽  
Elastic Modulus ◽  
Elastic Moduli ◽  
X Ray Diffraction ◽  
Phase Constitution ◽  
X Ray ◽  
Β Phase ◽  
Ω Phase ◽  
Solution Treated ◽  
Α Phase

Phase constitution in the solution-treated and quenched state and the heat treatment behavior were investigated by electrical resistivity, hardness, and elastic modulus measurements, X-ray diffraction, and optical microscopy. Hexagonal martensite and the β phase were identified in the Zr-5mass%Nb alloy. β and ω phases were identified in the Zr-10 and 15mass%Nb alloys, and only the β phase was identified in the Ti-20Nb alloy. Resistivity at RT, Vickers hardness and elastic modulus increased up to 10Nb and then decreased dramatically at 15Nb. Above 15Nb, these values slightly decreased. The elastic moduli for 15Nb and 20Nb were 59.5 and 55.5 GPa, respectively. On isochronal heat treatment, the isothermal ω phase precipitated between 473 and 623 K and then the α phase precipitated in the 10Nb, 15Nb and 20Nb alloys.

Reduced electrical resistivity of reaction-sintered SiC by nitrogen doping

2008 ◽  
Vol 23 (4) ◽  
pp. 1020-1025 ◽  
Author(s):  
Young-Sam Jeon ◽  
Hyunho Shin ◽  
Young-Hyun Lee ◽  
Sang-Won Kang
Keyword(s):  
Heat Treatment ◽  
Electrical Resistivity ◽  
Photoelectron Spectroscopy ◽  
Nitrogen Doping ◽  
Nitrogen Atmosphere ◽  
X Ray Diffraction ◽  
Post Heat Treatment ◽  
X Ray ◽  
Sic Particles ◽  
Transmission Electron

A post heat treatment of reaction-sintered SiC at 1700 °C in nitrogen atmosphere significantly reduced electrical resistivity. A trace of insulating Si3N4 phase was detected via nitrogen heat treatment in high-resolution transmission electron microscopy observation; however, based on x-ray photoelectron spectroscopy, the evidence of nitrogen doping into SiC lattice has been claimed as the mechanism to the decreased resistivity. The increase of the total volume of SiC was apparent in x-ray diffraction during the nitrogen heat treatment, which was interpreted to stem from the growth of the nitrogen-doped intergranular SiC particles and surface doping of the primary SiC to reduce the contact resistance between the primary SiC particles.

Influence of Substitution of Fe by Mo on Heat Treatment Behavior in Ti-Mo-Fe Alloys

2021 ◽  
Vol 1016 ◽  
pp. 162-169
Author(s):  
Kyosuke Mizuta ◽  
Shotaro Miyake ◽  
Masahiko Ikeda ◽  
Masato Ueda
Keyword(s):  
Heat Treatment ◽  
Electrical Resistivity ◽  
Diffusion Coefficient ◽  
Vickers Hardness ◽  
Partial Substitution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Β Phase ◽  
Ti Alloys ◽  
Fe Alloys

In order to reduce the cost of β-type Ti alloys, the use of Fe as an alloying element has been studied. However, Fe is known to have a very high diffusion coefficient in β-Ti of about 2.6×10-12 m2/s at 1200 K, and its behavior during heat treatment is expected to be difficult to control. By contrast, Mo, which is also a β-stabilizing element, has a diffusion coefficient of only about 2.5×10-14 m2/s at 1200 K, i.e., roughly 100 times smaller than that of Fe1), 2). In this study, the effect of the partial substitution of Fe with Mo on the aging behavior of β-Ti alloys was investigated using X-ray diffraction, electric resistivity, and Vickers hardness measurements. Ti-Mo-Fe alloys were solution-treated by holding at 1173 K for 3.6 ks and then quenching in ice water. In the X-ray diffraction patterns for the resulting samples, only peaks associated with the β phase were identified. It was found that the electrical resistivity and Vickers hardness decreased with increasing Mo content. As the Mo-to-Fe ratio increased, the decrease in electrical resistivity and the increase in Vickers hardness occurred later during the isothermal aging process. This was due to a delay in isothermal ω-phase precipitation.

Microstructural evolution of Sn–Ag–Cu–Al solder with respect to Al content and heat treatment

2002 ◽  
Vol 17 (9) ◽  
pp. 2386-2393 ◽  
Author(s):  
Kwang-Lung Lin ◽  
Chih-Chun Hsiao ◽  
Kaug-I Chen
Keyword(s):  
Heat Treatment ◽  
Microstructural Evolution ◽  
Eutectic Temperature ◽  
Melting Behavior ◽  
X Ray Diffraction ◽  
X Ray ◽  
Al Content ◽  
Sn Whiskers ◽  
Treatment Conditions ◽  
Differential Scanning Colorimetry

The Pb-free Sn–Ag–Cu–Al solders were investigated for microstructural evolution with respect to Al% and heat treatment. The Al% varies from 0.1% to 0.45% while the contents of Ag are 3.1%–2.53% and of Cu are 0.41%–0.33%. Differential scanning colorimetry (DSC) was applied to identify the melting behavior. A monotectic temperature of 224 °C and a eutectic temperature of 220 °C are deduced from the DSC results. The microstructure was characterized with x-ray diffraction and scanning electron microscopy-energy dispersive spectroscopy. Ag3Sn and the γ2 phase of Al–Cu system are the intermetallic compounds formed in the as-cast solders. Cu6Sn5 formed upon heat treatment for 1000 h at 150 °C in the 0.45 Al-containing solder, while not found in the other solders or other heat treatment conditions. Sn whiskers were detected in a 0.45 Al-containing specimen after aging for 50 h.

Development of Low-Cost Titanium-Manganese Shape Memory Alloys

2018 ◽  
Vol 941 ◽  
pp. 1254-1259
Author(s):  
Masahiko Ikeda ◽  
Masato Ueda
Keyword(s):  
Heat Treatment ◽  
Low Cost ◽  
Liquid Nitrogen Temperature ◽  
Al Alloys ◽  
X Ray Diffraction ◽  
Al Content ◽  
Orthorhombic Martensite ◽  
Β Phase ◽  
Heat Treated ◽  
Ice Water

Ti alloys are attractive materials for such applications, they are expensive due to the costly alloying elements such as Nb or Mo. The present authors have adopted Mn as a low-cost alloying element, and melted Ti-7, 7.5 and 8 mass%Mn-1.5 and 3mass%Al alloys using a laboratory-scale arc furnace. All specimens prepared from bottom ingots were heat treated at 1223 K for 3.6 ks and quenched in ice water. In the 7 and 7.5Mn-Al alloys, the β phase and orthorhombic martensite were identified using X-ray diffraction. In the 8Mn-Al alloys, only the β phase was identified. In the 7, 7.5, and 8Mn-Al alloys, the electrical resistivity at room and liquid nitrogen temperature increased with increasing Al content due to dissolution of Al into the β phase, whereas the Vickers hardness decreased with increasing Al content due to decreasing formation of athermal omega by the addition of Al. Heat treatment at 673 K for 60 s almost completely returned deformed Ti-7 and 7.5Mn-3Al specimens to their original shapes, and heat treatment at 773 K for 60 s almost returned deformed Ti-8Mn-Al specimens to their original shapes.

scholarly journals X-ray Determination of Compressive Residual Stresses in Spring Steel Generated by High-Speed Water Quenching

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1154
Author(s):  
Diego E. Lozano ◽  
George E. Totten ◽  
Yaneth Bedolla-Gil ◽  
Martha Guerrero-Mata ◽  
Marcel Carpio ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Residual Stresses ◽  
High Speed ◽  
Spring Steel ◽  
X Ray Diffraction ◽  
Laboratory Equipment ◽  
X Ray ◽  
Water Chamber ◽  
Hardened Case ◽  
Compressive Residual Stresses

Automotive components manufacturers use the 5160 steel in leaf and coil springs. The industrial heat treatment process consists in austenitizing followed by the oil quenching and tempering process. Typically, compressive residual stresses are induced by shot peening on the surface of automotive springs to bestow compressive residual stresses that improve the fatigue resistance and increase the service life of the parts after heat treatment. In this work, a high-speed quenching was used to achieve compressive residual stresses on the surface of AISI/SAE 5160 steel samples by producing high thermal gradients and interrupting the cooling in order to generate a case-core microstructure. A special laboratory equipment was designed and built, which uses water as the quenching media in a high-speed water chamber. The severity of the cooling was characterized with embedded thermocouples to obtain the cooling curves at different depths from the surface. Samples were cooled for various times to produce different hardened case depths. The microstructure of specimens was observed with a scanning electron microscope (SEM). X-ray diffraction (XRD) was used to estimate the magnitude of residual stresses on the surface of the specimens. Compressive residual stresses at the surface and sub-surface of about −700 MPa were obtained.

scholarly journals Impact of high temperatures on aluminoceladonite studied by Mössbauer, Raman, X-ray diffraction and X-ray photoelectron spectroscopy

2021 ◽  
Author(s):  
Mariola Kądziołka-Gaweł ◽  
Maria Czaja ◽  
Mateusz Dulski ◽  
Tomasz Krzykawski ◽  
Magdalena Szubka
Keyword(s):  
Photoelectron Spectroscopy ◽  
Integral Intensity ◽  
Photoelectron Spectra ◽  
X Ray Diffraction ◽  
Structural Reorganization ◽  
Oh Groups ◽  
X Ray ◽  
Al Content ◽  
Integral Intensity Ratio ◽  
Higher Temperature

AbstractMössbauer, Raman, X-ray diffraction and X-ray photoelectron spectroscopies were used to examine the effects of temperature on the structure of two aluminoceladonite samples. The process of oxidation of Fe2+ to Fe3+ ions started at about 350 °C for the sample richer in Al and at 300 °C for the sample somewhat lower Al-content. Mössbauer results show that this process may be associated with dehydroxylation or even initiate it. The first stage of dehydroxylation takes place at a temperature > 350 °C when the adjacent OH groups are replaced with a single residual oxygen atom. Up to ~500 °C, Fe ions do not migrate from cis-octahedra to trans-octahedra sites, but the coordination number of polyhedra changes from six to five. This temperature can be treated as the second stage of dehydroxylation. The temperature dependence on the integral intensity ratio between bands centered at ~590 and 705 cm−1 (I590/I705) clearly reflects the temperature at which six-coordinated polyhedra are transformed into five-coordinated polyhedra. X-ray photoelectron spectra obtained in the region of the Si2p, Al2p, Fe2p, K2p and O1s core levels, highlighted a route to identify the position of Si, Al, K and Fe cations in a structure of layered silicates with temperature. All the measurements show that the sample with a higher aluminum content and a lower iron content in octahedral sites starts to undergo a structural reorganization at a relatively higher temperature than the less aluminum-rich sample does. This suggests that iron may perform an important role in the initiation of the dehydroxylation of aluminoceladonites.

Effect of Solution Treatment on Microstructures and Hardness of Mg-Gd-Y-Zr Alloy

2014 ◽  
Vol 937 ◽  
pp. 182-186
Author(s):  
Quan An Li ◽  
Lei Lei Chen ◽  
Wen Chuang Liu ◽  
Xing Yuan Zhang ◽  
Hui Zhen Jiang
Keyword(s):  
Vickers Hardness ◽  
Cast Alloy ◽  
Solution Treatment ◽  
Hardness Measurement ◽  
Solution Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solution Treated ◽  
Primary Particles ◽  
Zr Alloy

The influence of the solution treatment (at the temperature of 500-520°C for 4-12 h) on microstructures and mechanical properties of Mg-Gd-Y-Zr alloy was investigated by means of optical microscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Vickers hardness measurement. The as-cast alloy contains a microstructure consisting of α-Mg matrix, Mg5Gd phase and Mg24Y5phase. With increasing solution temperature and time, the quantity of the primary particles (Mg5Gd and Mg24Y5) in the alloy continually decreased, and the degree of recrystallization gradually increased, which result in the gradual decrease of the Vickers hardness of the solution-treated alloys.

Sign in / Sign up

Export Citation Format

Share Document